The x2 is at a lake home garage connected to the house and boat is very difficult to maneuver and tower is down so it is not easy. I failed to put in my first post "I know,I know, I know it is better to drain it" but that wasn't my question.

The x2 is at a lake home garage connected to the house and boat is very difficult to maneuver and tower is down so it is not easy. I failed to put in my first post "I know,I know, I know it is better to drain it" but that wasn't my question.

Unless you can be absolutely sure it can't possibly freeze, under any circumstances, go ahead. You didn't post anything about the tower, garage, etc, so I based my answer on easier access but if you don't want a bad wake-up call in spring, I still recommend draining it.

Besides risk of freezing, I would think that water in the system would promote internal rusting of the engine....that's why I always drain mine and refill with -60 West marine anti-freeze. It has corrosion inhibitors in it according to the label.

Did some research on this this year and you could do a number of things if your concerned with corrosion. #1 - the moment water touches iron/steel it begins to rust. There's only so much oxygen dissolved in the water and after a certain period of time the rust reaction would stop. #2 - You could run some "Evaporust" thru your cooling jacket and let it sit overnight. It's non-corrosive and gasket safe to remove rust from your water jacket. It's pricey but it works. 5 gallons will cost you about $100. I like it because I believe it will keep the water passages clear. I also now wet store my block because of the corrosion inhibitors.

That being said - once you drop her back in the water the rust cycle starts all over again. I would to buy aluminum exhaust manifolds and risers - but the price so high.

JimN - which year has an aluminum block and heads?

__________________...A bad day water skiing still beats a good day at work...1995 Pro Star 205....

Besides risk of freezing, I would think that water in the system would promote internal rusting of the engine....that's why I always drain mine and refill with -60 West marine anti-freeze. It has corrosion inhibitors in it according to the label.

Cast iron rusts and there's not a thing we can do about it. Even if it's filled with A/F that has rust-inhibitors, it still rusts because the A/F has water in it but the first time fresh water goes in after the winter, the rust is flushed out. With water left inside, there's a lot more corrosion going on. My jointer lives in the garage and I found out the hard way that I didn't wax the table when I winterized my table saw, planer, bandsaw, etc. The next time I uncovered it, I saw that the cast iron top was completely coated with rust and this reminds me- once it warms up today, I need to go out and wax the table saw and bandsaw tables.

Did some research on this this year and you could do a number of things if your concerned with corrosion. #1 - the moment water touches iron/steel it begins to rust. There's only so much oxygen dissolved in the water and after a certain period of time the rust reaction would stop. #2 - You could run some "Evaporust" thru your cooling jacket and let it sit overnight. It's non-corrosive and gasket safe to remove rust from your water jacket. It's pricey but it works. 5 gallons will cost you about $100. I like it because I believe it will keep the water passages clear. I also now wet store my block because of the corrosion inhibitors.

That being said - once you drop her back in the water the rust cycle starts all over again. I would to buy aluminum exhaust manifolds and risers - but the price so high.

JimN - which year has an aluminum block and heads?

LT-1 is the only engine MC used with aluminum heads, AFAIK. The plenum on the LTR is aluminum but I'm pretty sure there's no water passing through it.